<template>
  <div>
    <router-link 
    tag="div"
    to="/"
    class="header-abs" v-show="showAbs">
      <i class="iconfont header-abs-back">&#xe624;</i>
    </router-link>
    <div class="header-fixed" v-show="!showAbs" :style="fixedStyle">
      <router-link  
      tag="div"
      to="/"
      class="iconfont header-fixed-back">&#xe624;</router-link >
      景点详情
    </div>
  </div>
</template>

<script>
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      fixedStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll () {
      const top = document.documentElement.scrollTop;
      if(top>60){
        //console.log(top)
        let opacity = top / 140;
        this.fixedStyle.opacity = opacity
        this.showAbs = false
      }else{
        this.showAbs = true
      }
    }
  },
  activated () {
    window.addEventListener('scroll',this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll',this.handleScroll)
  }
}
</script>

<style lang="stylus" scoped>
@import '~styles/varibles.styl'
  .header-abs
    position: absolute
    left: .2rem
    top: .2rem
    width: .8rem
    height: .8rem
    line-height: .8rem
    border-radius: .4rem
    text-align: center
    background: rgba(0, 0, 0, .6)
    .header-abs-back
      color: #fff
      font-size: .4rem
      margin-left: -0.1rem
  .header-fixed
    z-index: 2
    position: fixed
    top: 0
    left: 0
    right: 0
    height: 0.86rem
    line-height: 0.86rem
    text-align: center
    color: #fff
    background: $bgColor
    font-size: .32rem
    .header-fixed-back
      position: absolute
      top: 0
      left: 0
      width: .64rem
      text-align: center
      font-size: .4rem
      color: #fff
</style>
